Allowance for Loan Losses Allowance for Losses on Lending-Related Commitments and Impaired Loans (Schedule of Aging of the Company's Loan Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	$ 77,710		$ 103,582
90+ days and still accruing	37,987		86,484
60-89 days past due	39,281		39,698
30-59 days past due	72,613		84,566
Current	14,408,516		12,928,703
Total loans	14,636,107		13,243,033
Loans, net of unearned income excluding covered loans, Nonaccrual	70,420		94,157
Loans, net of unearned income excluding covered loans, 90+ days past due and still accruing	20,148		30,202
Loans, net of unearned income excluding covered loans, 60-89 days past due and still accruing	37,977		33,821
Loans, net of unearned income excluding covered loans, 30-59 days past due and still accruing	67,778		76,629
Loans, net of unearned income excluding covered loans, current	14,213,075		12,661,793
Loans, net of unearned income, excluding covered loans	14,409,398		12,896,602
Covered loans, Nonaccrual	7,290		9,425
Covered loans, 90+ days past due and still accruing	17,839		56,282
Covered loans, 60-89 days past due and still accruing	1,304		5,877
Covered loans, 30-59 days past due and still accruing	4,835		7,937
Covered loans, Current	195,441		266,910
Covered loans	226,709		346,431
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	9,157		10,780
90+ days and still accruing	839		274
60-89 days past due	5,123		5,882
30-59 days past due	11,558		11,755
Current	3,897,717		3,224,996
Loans, net of unearned income, excluding covered loans	3,924,394		3,253,687
Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	26,605		46,658
90+ days and still accruing	10,976		18,812
60-89 days past due	12,232		15,394
30-59 days past due	27,887		29,870
Current	4,428,053		4,119,301
Loans, net of unearned income, excluding covered loans	4,505,753		4,230,035
Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	6,174		10,071
90+ days and still accruing	0		0
60-89 days past due	983		1,344
30-59 days past due	3,513		3,060
Current	705,623		704,662
Loans, net of unearned income, excluding covered loans	716,293		719,137
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, net of unearned income, excluding covered loans	483,542		434,992
Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	277		1,137
90+ days and still accruing	119		286
60-89 days past due	293		76
30-59 days past due	838		1,010
Current	149,485		164,979
Loans, net of unearned income, excluding covered loans	151,012		167,488
Commercial and industrial | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	9,132		10,143
90+ days and still accruing	474		0
60-89 days past due	3,161		4,938
30-59 days past due	7,492		7,404
Current	2,194,221		1,813,721
Loans, net of unearned income, excluding covered loans	2,214,480		1,836,206
Franchise | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		0
90+ days and still accruing	0		0
60-89 days past due	308		400
30-59 days past due	1,219		0
Current	250,673		219,983
Loans, net of unearned income, excluding covered loans	252,200		220,383
Mortgage warehouse lines of credit | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		0
90+ days and still accruing	0		0
60-89 days past due	0		0
30-59 days past due	0		0
Current	139,003		67,470
Loans, net of unearned income, excluding covered loans	139,003		67,470
Community Advanatage - homeowners association | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		0
90+ days and still accruing	0		0
60-89 days past due	0		0
30-59 days past due	0		0
Current	106,364		90,894
Loans, net of unearned income, excluding covered loans	106,364		90,894
Aircraft | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		0
90+ days and still accruing	0		0
60-89 days past due	0		0
30-59 days past due	0		0
Current	8,065		10,241
Loans, net of unearned income, excluding covered loans	8,065		10,241
Asset-based lending | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	25		637
90+ days and still accruing	0		0
60-89 days past due	1,375		388
30-59 days past due	2,394		1,878
Current	802,608		732,190
Loans, net of unearned income, excluding covered loans	806,402		735,093
Tax exempt | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		0
90+ days and still accruing	0		0
60-89 days past due	0		0
30-59 days past due	0		0
Current	217,487		161,239
Loans, net of unearned income, excluding covered loans	217,487		161,239
Leases | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		0
90+ days and still accruing	0		0
60-89 days past due	77		0
30-59 days past due	315		788
Current	159,744		109,043
Loans, net of unearned income, excluding covered loans	160,136		109,831
Other | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		0
90+ days and still accruing	0		0
60-89 days past due	0		0
30-59 days past due	0		0
Current	11,034		11,147
Loans, net of unearned income, excluding covered loans	11,034		11,147
PCI - commercial | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	[1]	0	[1]
90+ days and still accruing	365	[1]	274	[1]
60-89 days past due	202	[1]	156	[1]
30-59 days past due	138	[1]	1,685	[1]
Current	8,518	[1]	9,068	[1]
Loans, net of unearned income, excluding covered loans	9,223	[1],[2]	11,183	[1],[2]
Residential construction | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		149
90+ days and still accruing	0		0
60-89 days past due	250		0
30-59 days past due	76		0
Current	38,370		38,351
Loans, net of unearned income, excluding covered loans	38,696		38,500
Commercial construction | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	230		6,969
90+ days and still accruing	0		0
60-89 days past due	0		0
30-59 days past due	2,023		505
Current	185,513		129,232
Loans, net of unearned income, excluding covered loans	187,766		136,706
Land | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	2,656		2,814
90+ days and still accruing	0		0
60-89 days past due	0		4,224
30-59 days past due	2,395		619
Current	86,779		99,128
Loans, net of unearned income, excluding covered loans	91,830		106,785
Office | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	7,288		10,087
90+ days and still accruing	0		0
60-89 days past due	2,621		2,265
30-59 days past due	1,374		3,862
Current	694,149		626,027
Loans, net of unearned income, excluding covered loans	705,432		642,241
Industrial | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	2,392		5,654
90+ days and still accruing	0		0
60-89 days past due	0		585
30-59 days past due	3,758		914
Current	617,820		626,785
Loans, net of unearned income, excluding covered loans	623,970		633,938
Retail | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	4,152		10,862
90+ days and still accruing	0		0
60-89 days past due	116		837
30-59 days past due	3,301		2,435
Current	723,919		642,125
Loans, net of unearned income, excluding covered loans	731,488		656,259
Multi-family | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	249		2,035
90+ days and still accruing	0		0
60-89 days past due	249		0
30-59 days past due	1,921		348
Current	603,323		564,154
Loans, net of unearned income, excluding covered loans	605,742		566,537
Mixed use and other | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	9,638		8,088
90+ days and still accruing	0		230
60-89 days past due	2,603		3,943
30-59 days past due	9,023		15,949
Current	1,443,853		1,344,244
Loans, net of unearned income, excluding covered loans	1,465,117		1,372,454
PCI - commercial real-estate | Commercial real-estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	[1]	0	[1]
90+ days and still accruing	10,976	[1]	18,582	[1]
60-89 days past due	6,393	[1]	3,540	[1]
30-59 days past due	4,016	[1]	5,238	[1]
Current	34,327	[1]	49,255	[1]
Loans, net of unearned income, excluding covered loans	55,712	[1],[2]	76,615	[1],[2]
Residential real estate | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	15,502		14,974
90+ days and still accruing	0		0
60-89 days past due	267		1,689
30-59 days past due	6,315		5,032
Current	459,224		410,430
Loans, net of unearned income, excluding covered loans	481,308		432,125
PCI - residential real estate | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	[1]	0	[1]
90+ days and still accruing	549	[1]	1,988	[1]
60-89 days past due	0	[1]	0	[1]
30-59 days past due	0	[1]	0	[1]
Current	1,685	[1]	879	[1]
Loans, net of unearned income, excluding covered loans	2,234	[1],[2]	2,867	[1],[2]
Commercial insurance loans | Premium finance receivables
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	12,705		10,537
90+ days and still accruing	7,665		8,842
60-89 days past due	5,995		6,912
30-59 days past due	17,328		24,094
Current	2,307,140		2,117,180
Loans, net of unearned income, excluding covered loans	2,350,833		2,167,565
Life insurance loans | Premium finance receivables
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0		0
90+ days and still accruing	0		0
60-89 days past due	13,084		2,524
30-59 days past due	339		1,808
Current	1,870,669		1,495,460
Loans, net of unearned income, excluding covered loans	1,884,092		1,499,792
PCI - life insurance loans | Premium finance receivables
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	0	[1]	0	[1]
90+ days and still accruing	0	[1]	0	[1]
60-89 days past due	0	[1]	0	[1]
30-59 days past due	0	[1]	0	[1]
Current	393,479	[1]	423,906	[1]
Loans, net of unearned income, excluding covered loans	$ 393,479	[1],[2]	$ 423,906	[1],[2]

[1] PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. Loan agings are based upon contractually required payments. See Note 4 - Loans for further discussion of these purchased loans.

[2] PCI loans represent loans acquired with evidence of credit quality deterioration since origination, in accordance with ASC 310-30. See Note 4 - Loans for further discussion of these purchased loans.